The Collaborative International Dictionary of English v.0.48:

Acinetae \Ac`i*ne"t[ae]\ ([a^]s`[i^]*n[=e]"t[=e]), n. pl. [NL.,
   fr. Gr. 'akinhtos immovable.] (Zool.)
   A group of suctorial Infusoria, which in the adult stage are
   stationary. See Suctoria.
   [1913 Webster]